at a candidate's forum on the univision spanish tv network, president obama expressed frustration he hasn't done more on a key issue for latinos, immigration reform. >> and the most important lesson i've learned is that you can't change washington from the inside, you can only change it from the outside. >> reporter: republican mitt romney pounced on that explanation. >> the president today threw in the white flag of surrender again. his surrender was, yes, we can. his slogan now is, no, i can't. this is time for a new president. >> reporter: but romney's tone has suddenly shifted. >> it's time to put the politics aside. >> reporter: that change follows a rough few weeks now showing in the latest nbc news wall street journal marist poll. the president now leading romney by 8 points in iowa and 5 points in colorado and wisconsin. and wisconsin, republican vp candidate paul ryan's home state, is one of the battle grounds the republicans need to keep in place. >> all right. brian mooar there for us in washington. brian, thank you. >>> meanwhile, with just seven days to go before electio